If you are looking for an effective way to permanently remove highly sensitive files, then file shredding is one way that can help you meet your goal. And, the best way you can perform this operation is by using Kernel File Shredder software.
If you want to delete a file or a folder permanently then you have to delete it from the Recycle Bin or use Shift + Delete key but it does not simply means that the file has got deleted permanently.
Your deleted data from computer are not permanently removed but they are stored somewhere on the hard disk and they can be recovered anytime by using a data recovery tool. You need a file shredder tool to delete files permanently.